A charge-discharge equalization control method and system based on multi-module battery pack

Abstract

The application discloses a charging and discharging equalization control method and system based on a multi-module battery pack, relates to the technical field of charging and discharging control, and comprises the following steps: monitoring state parameters of each battery module in real time; the state parameters comprise voltage, current and residual power; the total capacity and the current residual power of a battery pack of each battery module are calculated based on a preset SOC dynamic algorithm and the state parameters, and the SOC of the battery pack is obtained; charging equalization management and discharging equalization management are performed on the multiple battery modules according to a preset battery equalization control strategy, and each battery module is associated with an address number. The application improves the stability and reliability of the battery pack in the parallel connection scene of the multi-module battery pack.

Description

Technical Field

[0001] This application relates to the field of charge and discharge control technology, and in particular to a charge and discharge equalization control method and system based on a multi-module battery pack. Background Technology

[0002] In the scenario of parallel connection of multi-module battery packs, although the existing SOC (State of Charge, the current remaining power of the battery) calculation function and power balancing technology have been applied to some extent, there are still some shortcomings.

[0003] Regarding the SOC computing function, its shortcomings are mainly reflected in the following aspects:

[0004] Issues with accuracy and response speed: Some current SOC calculation methods may be affected by factors such as battery aging and temperature changes, resulting in certain errors in the calculation results. These errors may affect the decisions of the battery management system, thereby affecting the performance and lifespan of the battery pack. Furthermore, during the rapid charging and discharging of the battery pack, there may be a certain delay in SOC calculation, which may lead to an untimely response from the battery management system.

[0005] As for power balancing technology, its shortcomings are mainly reflected in:

[0006] Efficiency issues: Current power balancing technology may not be able to effectively balance the power between individual battery modules, which can limit the overall performance of the battery pack in applications requiring rapid response.

[0007] In summary, the stability and reliability of battery packs in parallel multi-module battery pack scenarios are not ideal, and there is room for improvement. Summary of the Invention

[0008] To improve the stability and reliability of battery packs in parallel multi-module battery pack scenarios, this application provides a charge-discharge equalization control method and system based on multi-module battery packs.

[0009] Firstly, the objective of this invention is achieved through the following technical solution:

[0010] A charge-discharge equalization control method based on a multi-module battery pack includes:

[0011] The status parameters of each battery module are monitored in real time; these status parameters include voltage, current, and remaining power.

[0012] The total battery pack capacity and current remaining power of each battery module are calculated based on the preset SOC dynamic algorithm and the state parameters to obtain the battery pack SOC.

[0013] Based on a preset battery balancing control strategy, multiple battery modules are managed for charging and discharging balancing, and each battery module is associated with an address number.

[0014] The preset battery balancing control strategy includes:

[0015] In the static state, based on the current voltage of each battery module, the high-voltage module and the low-voltage module are determined, and the high-voltage module is controlled to charge the low-voltage module with constant current until the voltage difference between the high-voltage module and the low-voltage module is less than a preset voltage difference threshold.

[0016] During discharge, the battery modules are sorted by address number according to their battery pack SOC, and the highest-ranked battery module is selected to discharge to the external load first. If the battery pack SOC of the currently discharging battery module is lower than the preset percentage of the battery pack SOC of the currently ranked first battery module, or if the power drops to a low discharge threshold, the discharge is switched to the newly ranked first battery module.

[0017] During charging, the maximum charging current of each battery module is controlled to not exceed a preset charging current threshold.

[0018] By adopting the above technical solutions, the battery module is also called a battery pack or battery stack. Multi-module battery packs use stacking and parallel technology, which can increase battery capacity in scenarios where users require large-capacity batteries. This application provides an adaptive multi-module battery pack charge-discharge balancing control system, optimizing the power distribution among multiple battery modules. Specifically, a SOC dynamic algorithm is used to monitor the state parameters of each battery module in real time, including battery current, voltage, temperature, and remaining power, to facilitate the regulation of the power output of the multi-module battery pack. Simultaneously, a predefined battery balancing control strategy is used to perform one-to-one fine-grained control of the multi-module battery pack in different states: In the static state (no charging or discharging), the SOC of the battery pack in multiple battery modules is detected and determined, and internal charge-discharge balancing is performed, i.e., identifying the high-voltage module with high voltage and the low-voltage module with low voltage, and controlling the high-voltage module to charge the low-voltage module with constant current (e.g., maximum current 10A) until the voltage difference between the two is less than the preset value. A voltage difference threshold is set, indicating that the voltage difference between the two is very small and negligible, thus effectively achieving power balance among the various battery modules. Furthermore, in the discharge state, the battery modules are sorted by State of Charge (SOC), with address numbers serving as identifiers. This prioritizes the discharge of battery modules with higher remaining charge to external loads, and the remaining charge status of the remaining uncharged battery modules is updated in real time. When a currently discharging battery module no longer meets the discharge conditions, maintenance is considered to extend its lifespan. The system then immediately switches to the newly ranked top-ranked battery module for discharge, improving the discharge response efficiency of the multi-module battery pack and enhancing its stability and reliability. Finally, in the charging state, the multi-module battery pack activates a charging current limiting function, ensuring that the maximum charging current of each battery module does not exceed a preset charging current threshold (e.g., a maximum charging current of 10A). This not only prevents overcharging but also reduces potential energy consumption during charging, improving charging safety and efficiency.

[0019] In a preferred embodiment of this application, the step of sorting by address number according to the state of charge (SOC) of the battery packs of the multiple battery modules during discharge specifically includes:

[0020] During discharge, each battery module is sorted from highest to lowest based on its battery pack SOC and address number to obtain discharge sorting information; the battery module with the higher battery pack SOC ranks higher, and if two or more battery modules have the same battery pack SOC, the battery module with the smaller address number ranks higher.

[0021] The discharge sorting information is reordered and updated based on a preset reordering rule; the preset reordering rule includes the battery module with the highest sorting power being lower than the preset power percentage of the second-ranked battery module or the battery module currently discharging having a power level less than or equal to the low discharge threshold.

[0022] By adopting the above technical solution, the discharge sorting logic of the entire multi-module battery pack system is optimized. By combining the battery pack SOC and address number, the modules are sorted from high to low, so that the modules with higher capacity are discharged first. When multiple battery modules have the same SOC, the module with the smaller address number is selected for discharge first. At the same time, as the currently discharging battery module discharges, the current remaining capacity of the battery will gradually decrease. In order to improve energy utilization efficiency and reduce the impact of deep discharge on battery life, this application will re-sort and update the battery based on a preset re-sorting rule. When the capacity of the highest-ranked battery module (i.e. the battery module currently being discharged) is lower than the preset capacity percentage of the second-ranked battery module, or the capacity of the currently discharging battery module is less than or equal to the low discharge threshold (which helps to avoid deep discharge of battery modules), by updating the discharge sorting information in real time, it is helpful to avoid some modules being in a high-load working state for a long time, thereby balancing the workload of each module and indirectly extending the service life of the entire battery pack.

[0023] In a preferred embodiment of this application, each of the battery modules is connected to a discharge control switch and a charge control switch;

[0024] Before selecting the highest-ranked battery module for discharge, it is determined whether the discharge control switch corresponding to the highest-ranked battery module is in the open state. The discharge time is delayed for the first duration, and the discharge control switches of the other battery modules are controlled to be in the on / off state. The discharge control switch corresponding to the highest-ranked battery module is then controlled to close, and the discharge begins.

[0025] During charging, the voltage difference between the multiple battery modules is calculated, and it is determined whether the voltage difference is less than the preset voltage difference threshold. When the voltage difference between all the battery modules is less than the preset voltage difference threshold, the charging control switch of the battery module is closed to start charging.

[0026] By adopting the above technical solution, before selecting the highest-ranked battery module for discharge, it is checked whether the corresponding discharge control switch is in the open state, and an appropriate delay is set to ensure safe start-up. When discharge begins, the discharge control switches of other modules are turned off to ensure that only the currently selected module participates in the discharge process. At the same time, by calculating the voltage difference between each module and setting a preset voltage difference threshold, the charging control switch is closed uniformly when the voltage difference of all modules meets the condition, which ensures uniform current distribution during the charging process and reduces the risk of overcharging. By strictly controlling the state of each switch during the charging and discharging process, the system can maintain stable operation under various working conditions.

[0027] In a preferred embodiment, this application further includes:

[0028] Obtain battery pack configuration information and battery pack design parameters; based on the battery pack configuration information and battery pack design parameters, determine the first predicted power state of each battery module during charging or discharging and the second predicted power state when reaching equilibrium; based on the battery pack design parameters, the first predicted power state and the second predicted power state, generate charge and discharge power comparison information for adjusting the charge and discharge power of each battery module.

[0029] Obtain a reference range for charge and discharge power variation that represents the threshold of charge and discharge power variation, and generate a charge and discharge equalization control model based on the reference range for charge and discharge power variation and the charge and discharge power comparison information.

[0030] Obtain the first actual power state and input the first actual power state into the charge-discharge equalization control model to adjust the charge-discharge power of each battery module.

[0031] By adopting the above technical solution, the first predicted power state (initial state) and the second predicted power state (state when equalization is achieved) of each battery module during charging or discharging are accurately determined. By generating charging and discharging power comparison information for adjusting the charging and discharging power of each battery module, clear guidance is provided for subsequent power adjustment, ensuring that the working state of each battery module can be optimized. By generating a charging and discharging equalization control model that can dynamically adapt to the needs under different operating conditions, the flexibility and response speed of the system are improved. The actual measured first power state is input into the charging and discharging equalization control model to adjust the charging and discharging power of each battery module, thereby improving the battery power adjustment rate of the multi-module battery pack.

[0032] In a preferred embodiment of this application, the step of determining the first predicted power state of each battery module during charging or discharging and the second predicted power state when equalization is achieved, based on the battery pack configuration information and the battery pack design parameters, specifically includes:

[0033] The battery pack configuration information includes the module connection method, the rated voltage and capacity of each battery module, and the internal resistance of the battery pack; the design parameters include the total design capacity of the battery pack, the first design charge and discharge power, and the second design charge and discharge power.

[0034] Based on the first designed charging and discharging power, the internal resistance of the battery pack, and the module connection method, determine the first predicted power state of each battery module at the start of charging or discharging.

[0035] Based on the module connection method, the second designed charge and discharge power, the internal resistance of the battery pack, and the total designed capacity of the battery pack, the second predicted power state of each battery module when equilibrium is achieved is determined.

[0036] By adopting the above technical solution, based on the first designed charging and discharging power, the internal resistance of the battery pack, and the module connection method, the first predicted power state of each battery module at the start of charging or discharging is determined, so that the power of the multi-module battery pack can be reasonably distributed during the startup phase, avoiding the impact caused by sudden current changes; by judging the second predicted power state of each battery module when equilibrium is reached, it is ensured that the system can maintain a good equilibrium state after long-term operation, preventing individual modules from overcharging or undercharging; it is also beneficial to better adjust the charging and discharging power of each battery module.

[0037] In a preferred embodiment of this application, the step of generating charge / discharge power comparison information for adjusting the charge / discharge power of each battery module based on the battery pack design parameters, the first predicted power state, and the second predicted power state specifically includes:

[0038] The predicted time to reach equilibrium is obtained based on the total design capacity of the battery pack, the first predicted power state, and the second predicted power state; the design time to reach equilibrium is obtained based on the first designed charge and discharge power and the second designed charge and discharge power.

[0039] Based on the battery pack's designed charge and discharge power, the predicted time to reach equilibrium, and the designed time to reach equilibrium, the predicted charge and discharge power of each module is obtained.

[0040] Calculate the ratio of the first predicted power state to the second predicted power state to obtain the predicted power ratio used to predict the actual power state of the module;

[0041] Calculate the over-equilibrium time difference between the predicted equilibrium time and the designed equilibrium time, and calculate the charge / discharge power difference between the predicted charge / discharge power of each module and the designed charge / discharge power of the battery pack.

[0042] Based on the balance time difference and the charge / discharge power difference, a predicted charge / discharge power time correspondence is obtained to determine the actual charge / discharge power of each battery module.

[0043] Based on the predicted power ratio and the predicted charge / discharge power time correspondence, charge / discharge power comparison information is generated for adjusting the charge / discharge power of each battery module.

[0044] By adopting the above technical solutions and introducing detailed power state prediction and dynamic adjustment mechanisms, the energy management efficiency of multi-module battery packs is significantly improved. By accurately calculating and adjusting various key parameters in the charging and discharging process in real time, the system's flexibility and response speed are enhanced. By allocating charging and discharging power to individual battery modules, the risk of overcharging and discharging is reduced, effectively extending the battery pack's lifespan and lowering maintenance costs.

[0045] In a preferred embodiment of this application: when implementing the preset battery balancing control strategy, formula (1) is used to adjust the charging and discharging power P of each battery module. i Optimization and adjustments will be made:

[0046] P i =α×SOC i +β×T i +γ×R i +δ×V diff,i +∈

[0047] In the formula, i represents the battery module identifier; SOC i Indicates the current remaining battery power of the battery module; T i Indicates the temperature of the battery module; R i Indicates the degree of aging of the battery module; V diff,i denoted as the voltage difference between the i-th battery module and other modules; α, β, γ, δ are preset weighting coefficients; ∈ is a preset safety margin influence coefficient.

[0048] By adopting the above technical solution, the system comprehensively considers factors such as the current remaining power, temperature, aging degree, and voltage difference of the battery module. Based on the aging of the battery module during actual use or the complex charging and discharging environment, the system performs real-time adjustment calculations and power optimization adjustments, thereby improving the efficiency of power optimization adjustments for multi-module battery modules. Through preset weighting coefficients α, β, γ, and δ, the system reflects the influence of different factors on the final charging and discharging power, thus improving the adaptability and reliability of the charging and discharging power.

[0049] Secondly, the objective of this invention is achieved through the following technical solution:

[0050] A charge-discharge equalization control system based on a multi-module battery pack, applied to the charge-discharge equalization control method based on a multi-module battery pack as described above, the system comprising:

[0051] The status monitoring module is used to monitor the status parameters of each battery module in real time; the status parameters include voltage, current and remaining power.

[0052] The calculation module is used to calculate the total battery pack capacity and current remaining power of each battery module based on the preset SOC dynamic algorithm and the state parameters, so as to obtain the battery pack SOC;

[0053] The equalization control module is used to perform charging equalization management and discharging equalization management of multiple battery modules according to a preset battery equalization control strategy. Each battery module is associated with an address number.

[0054] The communication interface is used to receive external commands and send status parameter information.

[0055] Thirdly, the objective of this invention is achieved through the following technical solution:

[0056] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described charge-discharge equalization control method based on a multi-module battery pack.

[0057] Fourthly, the objective of this invention is achieved through the following technical solution:

[0058] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described charge-discharge equalization control method based on a multi-module battery pack.

[0059] In summary, this application includes at least one of the following beneficial technical effects:

[0060] 1. By introducing comprehensive real-time monitoring, dynamic SOC calculation, and efficient equalization control strategies, the energy management accuracy and safety of multi-module battery packs during charging and discharging processes are significantly improved;

[0061] 2. The introduction of detailed power state prediction and comparison information generation significantly improves the energy management accuracy of multi-module battery packs, enabling the system to maintain efficient energy conversion and storage under various complex conditions. By monitoring and adjusting the charging and discharging power change threshold and actual power state, the system's adaptability is enhanced, enabling it to respond quickly to environmental changes and load demands, ensuring stable power output. Attached Figure Description

[0062] Figure 1 This is a flowchart of a charge-discharge equalization control method based on a multi-module battery pack according to an embodiment of this application;

[0063] Figure 2 This is an address allocation process and discharge equalization process flowchart in a charge-discharge equalization control method based on a multi-module battery pack according to an embodiment of this application;

[0064] Figure 3 This is another flowchart of a charge-discharge equalization control method based on a multi-module battery pack in one embodiment of this application;

[0065] Figure 4 This is a schematic diagram of a device according to one embodiment of this application. Detailed Implementation

[0066] The present application will be further described in detail below with reference to the accompanying drawings.

[0067] In one embodiment, such as Figure 1 As shown, this application discloses a charge-discharge equalization control method based on a multi-module battery pack, which specifically includes the following steps:

[0068] S1: Real-time monitoring of the status parameters of each battery module.

[0069] In this embodiment, the status parameters include voltage, current, and remaining power; the status parameters of each battery module are read and recorded in real time using a BMS (Battery Management System).

[0070] S2: Calculate the total battery pack capacity and current remaining power of each battery module based on the preset SOC dynamic algorithm and state parameters to obtain the battery pack SOC.

[0071] In this embodiment, the SOC dynamic algorithm refers to the recursive estimation of SOC using a Kalman filter, which combines the advantages of the open-circuit voltage method and the ampere-hour integration method.

[0072] S3: Based on the preset battery equalization control strategy, multiple battery modules are managed for charging and discharging equalization. Each battery module is associated with an address number.

[0073] In this embodiment, each battery module has a different address number, and the size of the address numbers can be compared and distinguished.

[0074] Specifically, the preset battery balancing control strategy includes:

[0075] In the static state, based on the current voltage of each battery module, the high-voltage module and the low-voltage module are determined, and the high-voltage module is controlled to charge the low-voltage module with constant current until the voltage difference between the high-voltage module and the low-voltage module is less than the preset voltage difference threshold.

[0076] During discharge, the battery modules are sorted by address number according to their battery pack SOC, and the highest-ranked battery module is selected to discharge to the external load first. If the battery pack SOC of the currently discharging battery module is lower than the preset percentage of the battery pack SOC of the currently ranked first battery module, or if the power drops to a low discharge threshold, the system switches to the newly ranked first battery module for discharge.

[0077] Specifically, such as Figure 2 As shown, during the discharge state, the addresses of multiple battery modules are sorted according to their State of Charge (SOC), specifically including:

[0078] During discharge, each battery module is sorted from highest to lowest based on its battery pack SOC and address number to obtain discharge sorting information. Battery modules with higher battery pack SOC are ranked higher. If two or more battery modules have the same battery pack SOC, the battery module with the smaller address number is ranked higher. The discharge sorting information is reordered and updated based on preset reordering rules. The preset reordering rules include the battery capacity of the highest-ranked battery module being lower than the preset battery capacity percentage of the second-ranked battery module, or the battery capacity of the currently discharging battery module being less than or equal to a low discharge threshold.

[0079] During charging, the maximum charging current of each battery module is controlled to not exceed a preset charging current threshold.

[0080] In this embodiment, the preset percentage is 5%, and the low discharge threshold is 5%.

[0081] Furthermore, each battery module is connected to a discharge control switch and a charge control switch; the discharge control switch and the charge control switch are MOSFETs.

[0082] Before selecting the highest-ranked battery module for discharge, it is determined whether the discharge control switch corresponding to the highest-ranked battery module is in the open state. The first discharge time is delayed, and the discharge control switches of the other battery modules are controlled to be in the on / off state. The discharge control switch corresponding to the highest-ranked battery module is then controlled to close, and the discharge begins.

[0083] In this embodiment, the first discharge duration is 5 seconds; each battery module is equipped with a discharge control switch and a charging control switch.

[0084] During charging, the voltage difference between multiple battery modules is calculated, and it is determined whether the voltage difference is less than a preset voltage difference threshold. When the voltage difference between all battery modules is less than the preset voltage difference threshold, the charging control switch of the battery module is closed to start charging.

[0085] In this embodiment, the preset voltage difference threshold is set automatically based on the rated voltage of each battery module.

[0086] Furthermore, when implementing the preset battery balancing control strategy, formula (1) is used to determine the charging and discharging power P of each battery module. i Optimization and adjustments will be made:

[0087] P i =α×SOC i +β×T i +γ×R i +δ×V diff,i +∈(1)

[0088] In the formula, i represents the battery module identifier; SOC i Indicates the current remaining battery power of the battery module; T i Indicates the temperature of the battery module; R i Indicates the degree of aging of the battery module; V diff,i denoted as the voltage difference between the i-th battery module and other modules; α, β, γ, δ are preset weighting coefficients; ∈ is a preset safety margin influence coefficient.

[0089] In one embodiment, such as Figure 3 As shown, a charge-discharge equalization control method based on a multi-module battery pack further includes: S10: obtaining battery pack configuration information and battery pack design parameters, and determining the first predicted power state of each battery module and the second predicted power state when equalization is achieved based on the battery pack configuration information and battery pack design parameters.

[0090] In this embodiment, the battery pack configuration information includes the module connection method, the rated voltage and capacity of each battery module, and the internal resistance of the battery pack; the design parameters include the total design capacity of the battery pack, the first design charge / discharge power, and the second design charge / discharge power, wherein the first design charge / discharge power refers to the maximum charge / discharge power designed for the entire multi-module battery pack system, and the second design charge / discharge power refers to the maximum charge / discharge power designed for the balanced state; the first predicted power state refers to the prediction of the initial power state of each battery module based on the current battery pack configuration information and design parameters at the start of charging or discharging.

[0091] Specifically, step S10 includes:

[0092] S101: Based on the first design charge / discharge power, the internal resistance of the battery pack, and the module connection method, determine the first predicted power state of each battery module at the start of charging or discharging.

[0093] S102: Based on the module connection method, the second design charge and discharge power, the internal resistance of the battery pack, and the total design capacity of the battery pack, determine the second predicted power state of each battery module when equilibrium is achieved.

[0094] S20: Based on the battery pack design parameters, the first predicted power state, and the second predicted power state, generate charge and discharge power comparison information for adjusting the charge and discharge power of each battery module.

[0095] In this embodiment, the charge / discharge power comparison information includes a comparison table or information set, which is used to guide the adjustment of the charge / discharge power of each module.

[0096] Specifically, step S20 includes:

[0097] S201: Obtain the predicted time to reach equilibrium based on the total design capacity of the battery pack, the first predicted state of power, and the second predicted state of power; obtain the design time to reach equilibrium based on the first designed charge / discharge power and the second designed charge / discharge power.

[0098] Specifically, the amount of charge change required to go from the initial state to the equilibrium state is first calculated (the charge change value is equal to the total design capacity of the battery pack multiplied by the difference between the estimated state of charge of the first predicted power state and the second predicted power state). Then, the time to reach equilibrium is predicted to be equal to the charge change divided by the average current from the initial state to the equilibrium state. The average current from the initial state to the equilibrium state is equal to the average of the sum of the initial current and the current in the equilibrium state of the battery module.

[0099] S202: Based on the battery pack's designed charge and discharge power, predicted equalization time, and designed equalization time, obtain the predicted charge and discharge power of each module.

[0100] Specifically, based on the predicted and designed equalization time, the predicted charge and discharge power of each battery module at different stages is calculated; the average current of each battery module from the initial state to the equalization state is calculated; and the average voltage of the battery modules is collected, assumed to be a constant value (which can be adjusted according to the actual situation).

[0101] S203: Calculate the ratio of the first predicted power state to the second predicted power state to obtain the predicted power ratio used to predict the actual power state of the module.

[0102] S204: Calculate the over-equilibrium time difference between the predicted and designed equilibrium times, and calculate the charge / discharge power difference between the predicted charge / discharge power of each module and the designed charge / discharge power of the battery pack.

[0103] S205: Based on the difference in over-balance time and the difference in charge and discharge power, obtain the predicted charge and discharge power time correspondence for judging the actual charge and discharge power of each battery module.

[0104] S206: Based on the predicted power ratio and the corresponding relationship between predicted charge and discharge power time, generate charge and discharge power comparison information for adjusting the charge and discharge power of each battery module.

[0105] Specifically, a time-power relationship model is established to dynamically adjust the charging and discharging power of each battery module. To establish the correspondence between time and power, we need to divide time into multiple intervals and define a corresponding power range for each interval. Let's assume we define the time interval as Δt and divide the power into several intervals ΔP. i Establish a time-power correspondence table, take the over-balance time difference ΔT and the charge-discharge power difference ΔP as inputs, and output the predicted charge-discharge power in different time periods. Then calculate the time-power correspondence, which can be done using nonlinear interpolation or linear interpolation methods.

[0106] Taking linear interpolation as an example:

[0107] P(t)=P mod +(ΔP / ΔT)×(tT design )

[0108] In the formula, P mod The predicted charging and discharging power of each module can be calculated one-to-one based on the device identifier i during actual calculation; T design To design the equilibrium time, for each time interval t, the corresponding predicted charge / discharge power P(t) is calculated. In actual calculation, the calculation boundary conditions also need to be considered to ensure that the power value outside the time range (such as t less than 0 or t greater than the predicted equilibrium time) remains within a reasonable range. For example, when t is less than 0, P(t) can be set to be equal to the predicted charge / discharge power. When t is greater than the predicted equilibrium time, P(t) can be set to be equal to the predicted charge / discharge power of each battery module in the entire multi-module battery module system when it reaches the equilibrium state.

[0109] S30: Obtain the reference range of charge and discharge power change that represents the threshold of charge and discharge power change, and generate a charge and discharge equalization control model based on the reference range of charge and discharge power change and the charge and discharge power comparison information.

[0110] S40: Obtain the first actual power state and input the first actual power state into the charge-discharge equalization control model to adjust the charge-discharge power of each battery module.

[0111] In this embodiment, the first actual power state refers to the actual charging and discharging power of each battery module at present. The first actual power state of each battery module is obtained in real time using sensors or monitoring devices. The charge and discharge equalization control model is a mathematical model used to adjust the charging and discharging power of each module according to the actual power state.

[0112] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0113] In one embodiment, a charge-discharge equalization control system based on a multi-module battery pack is provided, which corresponds to the charge-discharge equalization control method based on a multi-module battery pack in the above embodiment.

[0114] A charge-discharge equalization control system based on a multi-module battery pack includes a state monitoring module, a calculation module, an equalization control module, and a communication interface. Detailed descriptions of each functional module are as follows:

[0115] The status monitoring module is used to monitor the status parameters of each battery module in real time; the status parameters include voltage, current and remaining power.

[0116] The calculation module is used to calculate the total battery pack capacity and current remaining power of each battery module based on the preset SOC dynamic algorithm and state parameters, so as to obtain the battery pack SOC;

[0117] The equalization control module is used to perform charging equalization management and discharging equalization management of multiple battery modules according to a preset battery equalization control strategy. Each battery module is associated with an address number.

[0118] The communication interface is used to receive external commands and send status parameter information.

[0119] For specific limitations regarding a charge-discharge equalization control system based on a multi-module battery pack, please refer to the limitations of a charge-discharge equalization control method based on a multi-module battery pack mentioned above, which will not be repeated here. Each module in the aforementioned charge-discharge equalization control system based on a multi-module battery pack can be implemented entirely or partially through software, hardware, or a combination thereof. Each module can be embedded in or independent of the processor in a computer device in hardware form, or it can be stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0120] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 4As shown, the computer device includes a processor, memory, network interface, and database connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and database. The internal memory provides the environment for the operation of the operating system and computer programs in the non-volatile storage media. The database stores SOC dynamic algorithms and preset battery equalization control strategies. The network interface communicates with external terminals via a network connection. When executed by the processor, the computer program implements a charge / discharge equalization control method based on a multi-module battery pack.

[0121] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to perform the following steps:

[0122] S1: Real-time monitoring of the status parameters of each battery module; status parameters include voltage, current, and remaining power;

[0123] S2: Calculate the total battery pack capacity and current remaining power of each battery module based on the preset SOC dynamic algorithm and state parameters to obtain the battery pack SOC;

[0124] S3: Based on the preset battery equalization control strategy, multiple battery modules are managed for charging and discharging equalization, and each battery module is associated with an address number.

[0125] The preset battery balancing control strategies include:

[0126] In the static state, based on the current voltage of each battery module, the high-voltage module and the low-voltage module are determined, and the high-voltage module is controlled to charge the low-voltage module with constant current until the voltage difference between the high-voltage module and the low-voltage module is less than the preset voltage difference threshold. In the discharge state, the battery modules are sorted by address number according to the battery pack SOC of multiple battery modules, and the battery module with the highest ranking is selected to discharge to the external load first. If the battery pack SOC of the currently discharging battery module is lower than the preset percentage of the battery pack SOC of the currently ranked first battery module, or if the power drops to the low discharge threshold, the system switches to the newly ranked first battery module for discharge.

[0127] During charging, the maximum charging current of each battery module is controlled to not exceed a preset charging current threshold.

[0128] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0129] S1: Real-time monitoring of the status parameters of each battery module; status parameters include voltage, current, and remaining power;

[0130] S2: Calculate the total battery pack capacity and current remaining power of each battery module based on the preset SOC dynamic algorithm and state parameters to obtain the battery pack SOC;

[0131] S3: Based on the preset battery equalization control strategy, multiple battery modules are managed for charging and discharging equalization, and each battery module is associated with an address number.

[0132] The preset battery balancing control strategies include:

[0133] In the static state, based on the current voltage of each battery module, the high-voltage module and the low-voltage module are determined, and the high-voltage module is controlled to charge the low-voltage module with constant current until the voltage difference between the high-voltage module and the low-voltage module is less than the preset voltage difference threshold. In the discharge state, the battery modules are sorted by address number according to the battery pack SOC of multiple battery modules, and the battery module with the highest ranking is selected to discharge to the external load first. If the battery pack SOC of the currently discharging battery module is lower than the preset percentage of the battery pack SOC of the currently ranked first battery module, or if the power drops to the low discharge threshold, the system switches to the newly ranked first battery module for discharge.

[0134] During charging, the maximum charging current of each battery module is controlled to not exceed a preset charging current threshold.

[0135] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0136] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0137] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A charge-discharge equalization control method based on a multi-module battery pack, characterized in that, include: Real-time monitoring of the status parameters of each battery module; The status parameters include voltage, current, and remaining power. The total battery pack capacity and current remaining power of each battery module are calculated based on the preset SOC dynamic algorithm and the state parameters to obtain the battery pack SOC. Based on a preset battery balancing control strategy, multiple battery modules are managed for charging and discharging balancing, and each battery module is associated with an address number. The preset battery balancing control strategy includes: In the static state, based on the current voltage of each battery module, the high-voltage module and the low-voltage module are determined, and the high-voltage module is controlled to charge the low-voltage module with constant current until the voltage difference between the high-voltage module and the low-voltage module is less than a preset voltage difference threshold. During discharge, the battery modules are sorted by address number according to their battery pack SOC, and the highest-ranked battery module is selected to discharge to the external load first. If the battery pack SOC of the currently discharging battery module is lower than the preset percentage of the battery pack SOC of the currently ranked first battery module, or if the power drops to a low discharge threshold, the discharge is switched to the newly ranked first battery module. During charging, the maximum charging current of each battery module is controlled to not exceed a preset charging current threshold. Each of the battery modules is connected to a discharge control switch and a charge control switch. Before selecting the highest-ranked battery module for discharge, it is determined whether the discharge control switch corresponding to the highest-ranked battery module is in the open state. The discharge time is delayed for the first duration, and the discharge control switches of the other battery modules are controlled to be in the on / off state. The discharge control switch corresponding to the highest-ranked battery module is then controlled to close, and the discharge begins. During charging, the voltage difference between the multiple battery modules is calculated, and it is determined whether the voltage difference is less than the preset voltage difference threshold. When the voltage difference between all the battery modules is less than the preset voltage difference threshold, the charging control switch of the battery module is closed to start charging.

2. The charge-discharge equalization control method based on a multi-module battery pack according to claim 1, characterized in that, In the discharge state, the address numbering is sorted according to the SOC of the battery pack of the multiple battery modules, specifically including: During discharge, each battery module is sorted from highest to lowest based on its battery pack SOC and address number to obtain discharge sorting information; the battery module with the higher battery pack SOC ranks higher, and if two or more battery modules have the same battery pack SOC, the battery module with the smaller address number ranks higher. The discharge sorting information is reordered and updated based on a preset reordering rule; the preset reordering rule includes the battery module with the highest sorting power being lower than the preset power percentage of the second-ranked battery module or the battery module currently discharging having a power level less than or equal to the low discharge threshold.

3. The charge-discharge equalization control method based on a multi-module battery pack according to claim 1, characterized in that, The method also includes: Obtain battery module configuration information and battery module design parameters, and based on the battery module configuration information and battery module design parameters, determine the first predicted power state of each battery module during charging or discharging and the second predicted power state when reaching equilibrium; Based on the battery module design parameters, the first predicted power state, and the second predicted power state, charge and discharge power comparison information is generated for adjusting the charge and discharge power of each battery module. Obtain a reference range for charge and discharge power variation that represents the threshold of charge and discharge power variation, and generate a charge and discharge equalization control model based on the reference range for charge and discharge power variation and the charge and discharge power comparison information. Obtain the first actual power state and input the first actual power state into the charge-discharge equalization control model to adjust the charge-discharge power of each battery module.

4. The charge-discharge equalization control method based on a multi-module battery pack according to claim 3, characterized in that, The step of determining the first predicted power state of each battery module during charging or discharging and the second predicted power state when equalization is achieved, based on the battery module configuration information and the battery module design parameters, specifically includes: The battery module configuration information includes the module connection method, the rated voltage and capacity of each battery module, and the internal resistance of the battery module; the design parameters include the total design capacity of the battery module, the first design charge and discharge power, and the second design charge and discharge power. Based on the first designed charging and discharging power, the internal resistance of the battery module, and the module connection method, determine the first predicted power state of each battery module at the start of charging or discharging. Based on the module connection method, the second designed charge and discharge power, the internal resistance of the battery module, and the total designed capacity of the battery module, the second predicted power state of each battery module when equilibrium is achieved is determined.

5. The charge-discharge equalization control method based on a multi-module battery pack according to claim 4, characterized in that, The step of generating charge / discharge power comparison information for adjusting the charge / discharge power of each battery module based on the battery module design parameters, the first predicted power state, and the second predicted power state specifically includes: The predicted time to reach equilibrium is obtained based on the total design capacity of the battery module, the first predicted power state, and the second predicted power state; the design time to reach equilibrium is obtained based on the first designed charge and discharge power and the second designed charge and discharge power. Based on the designed charge and discharge power of the battery module, the predicted time to reach equilibrium, and the designed time to reach equilibrium, the predicted charge and discharge power of each module is obtained. Calculate the ratio of the first predicted power state to the second predicted power state to obtain the predicted power ratio used to predict the actual power state of the module; Calculate the over-equilibrium time difference between the predicted equilibrium time and the design equilibrium time, and calculate the charge / discharge power difference between the predicted charge / discharge power of each module and the designed charge / discharge power of the battery module. Based on the balance time difference and the charge / discharge power difference, a predicted charge / discharge power time correspondence is obtained to determine the actual charge / discharge power of each battery module. Based on the predicted power ratio and the predicted charge / discharge power time correspondence, charge / discharge power comparison information is generated for adjusting the charge / discharge power of each battery module.

6. The charge-discharge equalization control method based on a multi-module battery pack according to claim 1, characterized in that, When implementing the preset battery balancing control strategy, formula (1) is used to determine the charging and discharging power of each battery module. Optimization and adjustments will be made: In the formula, i represents the battery module identifier; Indicates the current remaining power of the battery module; Indicates the temperature of the battery module; Indicates the degree of aging of the battery module; This represents the voltage difference between the i-th battery module and other modules; , , , These are preset weighting coefficients; It is the preset safety margin influence coefficient.

7. A charge-discharge equalization control system based on a multi-module battery pack, characterized in that, The system, applied to the charge-discharge equalization control method based on a multi-module battery pack as described in any one of claims 1-6, comprises: The status monitoring module is used to monitor the status parameters of each battery module in real time; the status parameters include voltage, current and remaining power. The calculation module is used to calculate the total battery pack capacity and current remaining power of each battery module based on the preset SOC dynamic algorithm and the state parameters, so as to obtain the battery pack SOC; The equalization control module is used to perform charging equalization management and discharging equalization management of multiple battery modules according to a preset battery equalization control strategy. Each battery module is associated with an address number. The communication interface is used to receive external commands and send status parameter information.

8. A computer device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the charge-discharge equalization control method based on a multi-module battery pack as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the charge-discharge equalization control method based on a multi-module battery pack as described in any one of claims 1 to 6.

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